Aasimar

Aasimar are the children of Humans and good(subtype) outsiders. Usually with a human mother. Sometimes when a human and an Aasimar mate they produce another Aasimar but this is very rare and most Aasimar are direct descendants of outsiders. These children grow up differently, from birth having a unexplainable grace about them. Its not always immediately apparent that a child is an Aasimar but usually the parents do know. There heritage becomes quite obvious due to one of two reasons. The first is that with how slowly Aasimar age they will very visibly remain younger than others there age. The second way is a lot les pleasant. The second way there heritage becomes painfully visible to all is via molting. Generally Aasimar are respected and mildly venerated due to there powerful heritage

Molting

The innate good aligned nature of there body can have very severe effects on Aasimar. If an Aasimar goes against there conscious there body starts to react. Slowly they will start to gain more and more features from there outsider parent. For example if there father is a Garuda(bird creature) they might start to grow feathers on there arms. Mostly this is seen as harmless however it can go much further. The molting of an Aasimar is tied to there conscious and there mental state. If the mental state of an Aasimar continues to decline or they continue acting against there conscious the effects can get much worse. Continuing with the Garuda example the Aasimar would grow feather all over there body eventually even losing the use of there fingers as there arms morph into full fledged wings. This can still go further. When an Aasimar has done terrible deeds they cannot forgive themselves for or has suffered immense trauma can eventually morph into a full fledged monster losing all reason. Even as a monster they will always keep that semblance of holiness and shine about them.
The process of molting is very slow and gradual, especially the process of reversing it. The example of your arms becoming wings might happen over the course of 2-4 years deppending on how gradual the decline of there mental state was. Getting rid of those wings might take 6-12 years once the Aasimars mental state is positive again.
What's important to realize here is that molting is linked to the mental state and conscious of a person. A psychopathic Aasimar serial killer who has no problem with his murders will not molt.
Generally those who are heavily molting are shunned from society due to there monstrous appearance. This then in turn worsens the Aasimars mental state advancing the Molting proces.
Not all Aasimar are willing to accept the signs of Molting. Many actively try to hide it. Either trough clothing or magic, or by actively harming themselves. With example of growing feathers on there arms an Aasimar might routinely painfully pluck there own feathers. This sort of behaviour doesn't solve the underlying problem and usually makes things worse in the long term.

Lifespan

Aasimar seem to age like regular humans at first but the proces drastically slows down. They spend the rest of there lives slowly aging to the visual age of 40 and die looking as such. Even in death there corpses don't decompose holding the same visage forever.

Mechanics

Aasimar become middle aged at 250 and live till 300+1d%years. They don't gain further penalties from age besides reaching middle age, Your allowed to take variant Aasimar heritages and are encouraged to do so. Your allowed to roll the d100 table if you replace your spell like ability. You get one roll no takesie backsie. Alternatively instead of rolling on the d100 table you can keep your spell like ability and choice one of the d100 abilities to gain for flavour. In this case the ability can't grant a numerical or potent bonus, your allowed to ripen fruits you touch but your not allowed to gain a +2 to your str score or get a breath weapon. You can use the alternative physical features as inspiration for how you look but do keep in mind your celestial ancestor and your mental state with molting. A lantern archon wouldn't grant you wings and if your at your mental 100% you wouldn't have feathers showing.

Civilization and Culture

Historical Figures

The most famous Aasimar have been the 5 true Tragodian Emperors. Whilst initially disliked by many there generally looked back on favourable due to there immense charisma and ability to lead. Even conquered cities saw great improvements in living standards and the abolishment of slavery was seen by many as proof that these great Emperors where able to go past innate human greed.

Interspecies Relations and Assumptions

Aasimar are generally looked favourable upon by most races. The non-human races generally see the possibility in them to rise above the innate human greed.

Average Height

They tend to be slightly taller than humans

Average Weight

They tend to weigh slightly less than humans